No Spark! What’s Wrong?

If you like to ride motorcycles, there is a very good chance that sooner or later you will experience a “No Spark” situation. The scope of this article will focus on visual observations, the use of a multimeter or bulb tester, and the appropriate process of elimination to determine why your motorcycle spark plug(s) is not firing correctly.

1) The easiest starting point is to remove one of the motorcycle’s spark plugs and re-attach the spark plug wire. Holding the loose plug by its ceramic insulator, make certain the plug’s metal base is well grounded. Then, have someone bump the ignition switch or kick starter while you observe the plug’s ground electrode. If you see a blue or yellow spark bridge the gap, then you should have adequate fire to ignite the fuel/air mixture in that cylinder. If not:

2) Be certain the motorcycle is turned on. That sounds simple but ignition switches can fail. Plus, on many newer models of street bikes, the motorcycle’s anti-theft system must receive a specified flow of juice or the engine will not start. This prevents a would-be thief from by-passing the switch and “hot wiring” the motorcycle’s ignition. With the key or switch in the “On” position, your multi-tester should display a positive electrical flow leaving the switch. If not, the switch may be broken or may have lost its ground.

3) Once you have determined that you have power from the switch to the coil, use your multimeter or bulb tester to ensure that the current leaving the coil is reaching the spark plug cap. With the tester attached, you should get an “on” and an “off” reading for each engine revolution as someone tries to start the motor. If so, replace the failed plug with a new plug and repeat Step 1. If you do not get an alternating flow of current, then the spark plug wire or spark plug cap may need to be replaced.

4) NOTE: On older motorcycles, you may also need to check the electrical flow on either side of the engine’s points and condenser. If the multi-tester stays “On” in Step 3 during cranking, the contact points are not closing correctly. If the tester stays “Off” in Step 3, the points may be stuck closed or the condenser may have a short. In either case, it’s best to replace the faulty ignition parts.

E3 motorcycle spark plugs feature our patented Edge-to-Edge DiamondFire technology and offer improved Energy, Efficiency and Ecology. Keep your wheels pointed at the road or the trail and “safe riding from all of us at E3 Spark Plugs.”